Manufactures of crop pick-ups used in the hay and forage industry have mainly used metal, usually steel, stripper bands to protect internal components, such as tooth bars, of the crop pick-up. In operation, the pick-up will sometimes impact a dense object, such as a rock for example, causing the steel band involved in the impact to become permanently deformed. Typically, the impact will occur on a lower surface of a given stripper band which results in the band being deformed in the upward direction, and, in some cases, deformed left or right depending on the location of the area of the band impacted by the dense object. Once deformed, the steel band can cause internal damage to pick-up components such as the pick-up teeth or the tooth bar as these components collide with the deformed steel band. Furthermore, these collisions create noise, undue wear to the steel band and pick-up components, and create sharp edge locations along the steel band. These sharp edge locations make service difficult since they can cut the hands of a person doing the service work. Another source of service difficultly resides in the fact that hardware must be loosened or removed from on top and underneath the pick-up in order to replace a damaged steel band or damaged components beneath the band.
In order to overcome the above-noted drawbacks associated with steel stripper bands, some manufactures in recent years have replaced the steel crop stripper bands entirely with plastic crop stripper bands. Examples of such plastic stripper bands are disclosed in US Patent Application Pub. No.: US 2003/0110752 published Jun. 19, 2003 and US Patent Application Pub. No.: US 2009/0025358 published Jan. 29, 2009. Crop stripper bands made entirely of plastic offer good impact resistance (bounce back) when coming into contact with dense objects as compared to steel and, if adjacent parts (teeth) or internal parts (tooth bars) contact a plastic crop stripper band, wear and noise is greatly reduced as compared to contact with a steel crop stripper band. Plastic crop stripper bands will also not develop the sharp edges that are common with steel bands when contacted by internal and adjacent parts. Furthermore, when it comes time to replace internal components of the pick-up, the fasteners holding a given stripper band to the pick-up support frame need only be removed from the upper leg since the plastic stripper band can be easily deflected out of the way while leaving the bottom fasteners intact.
While making the stripper bands entirely out of plastic greatly improves impact resistance, wear, noise generation, serviceability and quality, a stripper band made entirely of plastic lacks the load carrying capacity of steel which is required for picking up very dense windrows. An entirely plastic crop stripper has seen success in the crop merger industry because the crop being picked up is much less dense as it has not been previously gathered. Another drawback associated with plastic crop stripper bands is that thermal and ultraviolet fluctuations cause the stripper bands to warp, which not only results in the pick-up being aesthetically displeasing but also results in crop entanglement due to crop entering gaps created by the warped bands. In addition, conventional fasteners are still required to secure the plastic bands in place with it being challenging to achieve proper bolt torque without crushing plastic located in the clamp joint.
Although it is known to apply a thin strip of plastic to a metal stripper band (see the aforementioned US Patent Application Publication No.: US 2009/0025358), these plastic clad metal bands are still prone to being permanently deformed when impacted with a hard object.
Accordingly, the problem to be solved is to provide crop stripper bands having the desirable characteristics of the above-described plastic bands while avoiding the drawbacks.